Effect of the Turbulence–Chemistry Interaction in Packed-Bed Biomass Combustion

Abstract

Numerous studies in packed-bed biomass combustion modeling have been carried out, with the validation being usually performed against experimental data obtained in regions far from the bed. It is known, however, that in these regions standard modeling has a tendency to overpredict the solid and gas temperatures and the mixing rates of the gaseous species released from the packed-bed. This leads to an underprediction of the unburned hydrocarbon and soot concentrations in these regions, originating incorrect estimates of the pollutant emissions. Due to more and more stringent legislation, the combustion appliances need to improve their designs, for which deeper studies of the near-bed region modeling are necessary. This study seeks to find the main causes for the temperature and gaseous species misprediction in this region. Current biomass combustion models represent the gas–solid interaction by means of a porous medium, impeding the representation of the streaks with nonperfect mixed species that are known...